PIVOT-891 (more): Fix the up/down selection logic in TextArea to do the "right" thing
by remembering the "anchor" point where the selection started and reducing / enlarging
the area depending on whether you are on one side of the anchor or the other.  A
previous change fixed the left/right logic.  Further changes will make these same
changes to TextPane.

Probably need to check selection logic in lists and text input fields as well.



git-svn-id: https://svn.apache.org/repos/asf/pivot/branches/2.0.x@1460982 13f79535-47bb-0310-9956-ffa450edef68